The present invention relates to a system and method for regulating the operation of an irrigation system. More particularly, the invention pertains to a system and method for regulating the operation of an irrigation system which is responsive to user programmed information.
Automatic irrigation systems such as those employed for landscape and agricultural watering are well known in the art. Typical irrigation systems use a means of controlling the watering cycles via an automatic controller. The need to control watering cycles due to seasonal changing environmental conditions is important for saving costs, optimizing growing conditions, and preventing unsafe conditions.
Typically, a user will enter instructions into a microprocessor based controller that will cause the irrigation system to start irrigation at a certain time, on certain days, for a certain duration, according to the user's instructions. Irrigation may be based on “zones” in which a group of sprinkler heads discharge in unison, or sequentially, or a combination of both.
Typically, a user who programs the microprocessor in the summer month of July to deliver an irrigation event of a certain duration on certain days from a particular irrigation system, would, if reminded to attend to the issue, reduce that duration over the fall, winter, and spring months to take account of changing seasonal environmental conditions that can be expected to prevail in the vicinity of the irrigation system, and the user might reduce the duration accordingly each month, or shorter period, before increasing it again. Typically, however, many users tend to forget to downwardly adjust the irrigation duration after the hot summer months to account for the reduced evapo-transpiration rates over the following months. At best, a user will typically remember to adjust irrigation for some months or shorter period, but not others. As a result, the irrigation system continues to discharge water in irrigation during the fall, and winter at a rate that was selected to be suitable during the summer, or some other time that is inappropriate. This can be very wasteful, not to mention destructive in the case of certain crops, grasses, flowers, and shrubs that react adversely to over or under watering.
Consequently, solutions have been developed for taking into account actual environmental conditions prevailing, and for automatically adjusting irrigation duration to take account of changed conditions in real time. These solutions typically employ a sensor that monitors changes in environmental conditions in real time. A sensor may be located near an associated controller, and may be linked to the controller either by wireless communication or by physical connection. Such a sensor may measure actual precipitation, actual temperatures, actual wind speed, soil moisture, humidity, and other environmental factors, all in real time. Based on these measurements which are transmitted back to the controller, the controller uses preprogrammed logical algorithms and decides how to adjust a preprogrammed irrigation schedule to account for changed environmental conditions. For example, if high temperatures and dry conditions are recorded, irrigation duration may be increased. If wet or cold conditions are noted, irrigation may be reduced or suspended altogether.
However, such sensor based systems have drawbacks and disadvantages. They are notoriously complex, and difficult to calibrate and install. Typically, weather sensors are mounted where they are exposed to the elements and once mounted are not easily adjusted or manipulated. They add significantly to the cost of a controller system that must be preprogrammed to take into account a host of new variables and logic subroutines. They are prone to malfunction, and difficult to maintain in operation.
Accordingly, there is a need in the art for an irrigation controller that may be sold and used universally, that is easy to use, that is inexpensive to manufacture, that is easy to install, initialize, maintain, and operate, and that yet takes account of the fact that seasonal environmental conditions vary during the year in any location—and that, accordingly, enables the amount of irrigation in any location to be automatically varied for efficient use of the system. The present invention addresses these and other needs.